Acoustic/Instrumental Track with Whistling - Please Help!

[dollstarsugar]

I was out in a restaurant last night and heard a track that i recognise and really love but cannot find a trace of anywhere! Chances are it may've been on a commericial or something, i'm 99% sure it's a fairly modern track.
It's completely instrumental, kind of acoustic-y track and throughout it there's a guy whistling this tune over the top of it. It sounds like it should be a band like air or album leaf but i've had a quick search through their tracks and can't find it. Any help would be very much appreciated!